:root {
  --bg:       #0f1117;
  --surface:  #1a1d27;
  --border:   #2a2d3a;
  --accent:   #4f8ef7;
  --accent2:  #34d399;
  --warn:     #f59e0b;
  --text:     #e2e8f0;
  --muted:    #8892a4;
  --danger:   #f87171;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 14px;
  line-height: 1.5;
}

header {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  position: sticky;
  top: 0;
  z-index: 10;
}

header h1 {
  font-size: 18px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: -0.3px;
}

nav#home-nav {
  display: flex;
  gap: 8px;
}

nav#home-nav button {
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 4px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 13px;
  transition: all .15s;
}

nav#home-nav button.active,
nav#home-nav button:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(79,142,247,.08);
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 36px;
}

section h2 {
  font-size: 15px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: .6px;
  margin-bottom: 14px;
}

/* Cards */
.card-row {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px 20px;
  min-width: 160px;
  flex: 1;
}

.card .label {
  font-size: 12px;
  color: var(--muted);
  margin-bottom: 4px;
  text-transform: uppercase;
  letter-spacing: .5px;
}

.card .value {
  font-size: 26px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.1;
}

.card .sub {
  font-size: 12px;
  color: var(--muted);
  margin-top: 4px;
}

.card.accent  .value { color: var(--accent); }
.card.green   .value { color: var(--accent2); }
.card.warn    .value { color: var(--warn); }
.card.danger  .value { color: var(--danger); }

/* Chart */
.chart-container {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  position: relative;
  height: 260px;
}

#trends-canvas { width: 100% !important; height: 100% !important; }

/* Tables */
.splits-table-wrap,
#splits-table-wrap,
#history-table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid var(--border);
}

th {
  background: rgba(255,255,255,.03);
  color: var(--muted);
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .5px;
  padding: 10px 14px;
  text-align: right;
  white-space: nowrap;
}

th:first-child { text-align: left; }

td {
  padding: 9px 14px;
  text-align: right;
  border-top: 1px solid var(--border);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

td:first-child { text-align: left; color: var(--muted); }

tr:hover td { background: rgba(255,255,255,.025); }

td.hi { color: var(--accent2); font-weight: 600; }
td.lo { color: var(--danger); }

/* Tabs */
#tab-nav {
  display: flex;
  padding: 0 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.tab-btn {
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--muted);
  padding: 10px 18px;
  cursor: pointer;
  font-size: 14px;
  margin-bottom: -1px;
  transition: color .15s;
}

.tab-btn.active,
.tab-btn:hover { color: var(--accent); border-bottom-color: var(--accent); }

/* Compact cards (last month reference) */
.card.compact .value { font-size: 18px; }

/* Attribution events */
.event-list { margin-top: 12px; display: flex; flex-direction: column; gap: 6px; }
.event-item { font-size: 13px; color: var(--muted); }
.event-date { color: var(--text); font-weight: 600; margin-right: 8px; }

/* Upload form */
#upload-form { display: flex; flex-direction: column; gap: 14px; max-width: 480px; }
.upload-field { display: flex; flex-direction: column; gap: 6px; }
.upload-field label { font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .5px; }
.upload-field select,
.upload-field input[type="file"] {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  padding: 8px 12px;
  font-size: 14px;
}
#upload-btn {
  align-self: flex-start;
  background: var(--accent);
  border: none;
  border-radius: 6px;
  color: #fff;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  padding: 8px 20px;
  transition: opacity .15s;
}
#upload-btn:disabled { opacity: .5; cursor: default; }
#upload-result { margin-top: 12px; }
.upload-ok { color: var(--accent2); font-size: 14px; padding: 10px 0; }

/* Loading / error states */
.loading { color: var(--muted); padding: 20px; text-align: center; }
.error   { color: var(--danger); padding: 20px; text-align: center; }